KIEL, Wisconsin -- Todd and Melissa Puchalla struggled more than two years to raise Quita, the troubled teenager they’d adopted from Liberia. When they decided to give up the 16-year-old, they found new parents to take her in less than two days — by posting an ad on the Internet.

Nicole and Calvin Eason, an Illinois couple in their 30s, responded quickly. In emails, Nicole Eason assured Melissa Puchalla that she could handle the girl. “People that are around me think I am awesome with kids,” Eason wrote.

A few weeks later, on Oct. 4, 2008, the Puchallas drove from their Wisconsin home to Westville, Ill. The handoff took place at the Country Aire Mobile Home Park, where the Easons lived.

No attorneys or child welfare officials were present. The Puchallas simply signed a notarized statement declaring these virtual strangers to be Quita’s guardians. The visit lasted a few hours. It was the first and the last time the couples would meet.

To Melissa Puchalla, the Easons “seemed wonderful.” Had she vetted them more closely, she might have discovered what Reuters would learn:

· Child welfare authorities had taken away both Nicole Eason’s biological children years earlier. A sheriff’s deputy wrote that the couple had “violent tendencies.”

· The only official document attesting to their parenting skills - one purportedly drafted by a social worker who had inspected the Easons’ home - was fake, created by the Easons themselves.

· Nicole Eason and another man, Randy Winslow, had taken in a 10-year-old boy advertised online in 2006. Later, Winslow was arrested and is now serving a 20-year sentence in federal prison for sending and receiving child pornography.

Samantha Sais / Reuters

Nicole Eason has taken in more than a half-dozen children, many from failed international adoptions, during the past decade.

On Quita’s first night with the Easons, her new guardians told her to join them in their bed, Quita says today. The Easons say they never shared their bed with any child they took in, but Quita remembers it vividly; Nicole, she says, slept naked.

Within a few days of dropping Quita there, Melissa Puchalla couldn’t reach the Easons and had no idea what had become of the girl. About two weeks passed before authorities located her, took her from the Easons and sent her back to Wisconsin - alone, on a bus.

No further action was taken by authorities in Illinois, Wisconsin or New York.

When she arrived in the United States, Quita says, she thought she was “coming to a nicer place, a safer place. It didn’t turn out that way,” she says today. “It turned into a nightmare.”

The teenager had been tossed into America’s underground market for adopted children, a loose Internet network where desperate parents seek new homes for kids they regret adopting. Like Quita, now 21, these discarded children are often the casualties of international adoptions gone sour.

Through Yahoo and Facebook groups, parents and others advertise unwanted children and then pass them to strangers with little or no government scrutiny, sometimes illegally, a Reuters investigation has found.

It is a largely lawless marketplace where the needs of parents are often put ahead of the welfare of the orphans they brought to America. One government official alerted child protection workers across the United States that the practice is “placing children in grave danger.” Even so, no laws specifically address it, and no government agency monitors the bulletin boards.

The practice is called “private re-homing,” a term typically used by owners seeking new homes for their pets. Based on solicitations posted on one of eight similar online bulletin boards, the parallels are striking.

Watch "Today" and "NBC Nightly News with Brian Williams" for more on re-homing.

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A woman who said she is from Nebraska offered an 11-year-old boy she had adopted from Guatemala. “I am totally ashamed to say it, but we do truly hate this boy!” she wrote in a July 2012 post.

Reuters analyzed 5,029 posts from a five-year period on one Internet message board, a Yahoo group. On average, a child was advertised for re-homing there once a week. Most of the children ranged in age from 6 to 14 and had been adopted from abroad - from countries such as Russia and China, Ethiopia and Ukraine. The youngest was 10 months old. One participant referred to the re-homing forums as “‘farms’ in which to select children.”

A 10-year-old boy from the Philippines and a 13-year-old boy from Brazil each were advertised three times. So was a girl from Haiti. She was offered for re-homing when she was 14, 15 and 16 years old.

“I would have given her away to a serial killer, I was so desperate,” one mother wrote in a March 2012 post about her 12-year-old daughter.

After learning what Reuters found, Yahoo took down Adopting-from-Disruption, the six-year-old bulletin board. A spokeswoman said Yahoo also took down five other groups that Reuters identified.

A similar forum on Facebook, Way Stations of Love, remains active but private. A Facebook spokeswoman says the page shows “that the Internet is a reflection of society.”

Some re-homed children have endured severe abuse. One girl adopted from China and later sent to a second home said she was made to dig her own grave. Another re-homed child, a Russian girl, recounted how a boy in one house urinated on her after the two had sex; she was 13 at the time and was re-homed three times in six months.

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“There’s hundreds of people looking for new homes for kids,” says Glenna Mueller, an adoptive mother who advertised her 10-year-old son online.

Parents who offer their children on the Internet say they have limited options. On the bulletin boards, parents talk of children becoming abusive and violent, terrorizing them and other kids in the household. “People get in over their heads,” says Tim Stowell, an adoptive parent who created the Facebook group last year.

UNKNOWN DANGERS

Because private re-homings often bypass the government, the only vetting of prospective families is done by parents who want to get rid of children. That creates the possibility kids could fall into the hands of dangerous people. In the group Reuters analyzed, more than half of the children were described as having some sort of special need. About 18 percent were said to have a history that included sexual or physical abuse.

“If you advertise details of things like their substance abuse or sexually acting out, that’s waving a red flag” for predators, says Michael Seto, an expert on the sexual abuse of children at the Royal Ottawa Health Care Group in Canada.

In July 2006 - within hours of posting an ad for the 10-year-old boy she had adopted out of the U.S. foster care system - Glenna Mueller met Nicole Eason and Eason’s friend Winslow outside a hotel near Mueller’s Appleton, Wisconsin home. There, Mueller gave them the boy, along with a note saying they could care for him. “I wanted this child gone,” says Mueller, a former daycare provider.

A few months later, she took the boy back after a Wisconsin child welfare worker told Mueller she could be arrested for not involving state authorities in the custody transfer, she says. The boy later told her he had spent most of his time in Illinois with Winslow.

Court documents show Winslow, then 41, had been trading child pornography during the boy’s time with him in Illinois. In the months after the boy left, Winslow spent time in a chat room where he graphically boasted of molesting boys and explained how to keep the abuse quiet: “Just have to raise them to think its fine and not to tell anyone,” he wrote in a chat with an undercover federal agent.

Now in federal prison in Elkton, Ohio, Winslow declined requests for an interview. The boy turned 18 a few days ago. His foster parents declined to make him available for an interview.

MEAGER SAFEGUARDS

There is one potential safeguard for children: an agreement among states called the Interstate Compact on the Placement of Children, or ICPC. It requires that if a child is to be transferred outside of the family to a new home in a different state, parents who take in and give away the child must notify authorities in both states. That way, the prospective parents can be vetted.

Not until January 2011 did an official responsible for overseeing the U.S. child protection compact call attention to the “grave danger” of the online network. In a nationwide alert, an administrator for the ICPC warned that adoptive parents were sending children to live with people they met on the Internet. The practice, the official wrote, “puts children at substantial risk.” Despite the urgency, the official, Stephen Pennypacker, says states still cannot account for such custody transfers.

International adoptees are especially susceptible to being re-homed. Reuters found that at least 70 percent of children offered on the Yahoo bulletin board were advertised as foreign-born. Americans have adopted about 243,000 children from abroad since the late 1990s, but no authorities systematically track what happens to those children after they arrive in the United States.

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Transfers such as those involving Nicole Eason – the woman who disappeared with Quita and took the 10-year-old boy in the hotel parking lot – might never be recorded.

Eason has succeeded in taking in at least six children through the Internet, despite her troubled history. In 2000, a report by Massachusetts officials shows, Eason’s biological daughter was taken away after the 9 month old was admitted to the hospital with a broken femur “for which the parents had no explanation.”

In 2002, about a week after Nicole’s second child was born, South Carolina authorities removed the newborn boy from the Eason home, sheriff’s records show. Authorities cited the neglect investigation of the Easons in Massachusetts and the “deplorable” conditions in the couple’s South Carolina home. “Parents have severe psychiatric problems as well with violent tendencies,” a deputy wrote in a March 2002 report.

In interviews with Reuters, the Easons said the two children again live with them. In truth, the couple never got them back, South Carolina and Massachusetts officials confirmed.

Eason described her parenting style this way: “Dude, just be a little mean, OK? … I’ll threaten to throw a knife at your ass, I will. I’ll chase you with a hose”

Asked to explain why officials in two states say her children had been permanently removed, Nicole Eason said someone was lying.

“I haven’t had problems with social services,” she said. “That’s what I’m claiming.”